Some of you might have seen this error after upgrading your DNN from v6 to v7. It’s a bit scarey because it means that no-one can log into your DNN instance, not even a super user. Troubleshooting must therefore begin on the hosting server. Check out the log files under .Portals_defaultLogs. For me the critical error was:

So first place to look is at the Stored Procedure called UpdateUser and see what it’s expecting. You can do this in SQL Server Management Studio, navigate to your DB, open programmability and expand Stored Procedures. Down towards the bottom is a SP called dbo.UpdateUser. Right click on it and select Modify and you can see the guts of what it does:

Thanks for this article. It isn’t the full solution, but it helped me figure out the underlying problem. The actual issue is that the AspNetMembershipProvider was moved to a different DLL in DotNetNuke 7, but the upgrade wizard does not remove the old version, and it does not update the web.config.